Advances in computer technology and software have made possible the creation of richly featured virtual characters capable of simulating interactivity with a human observer of the virtual character. The illusion of interactivity may be even greater when the virtual character appears to be independent of the display system generating it. For example, the virtual character may be shown as an image that appears to float in space. Moreover, the immersiveness of the experience for the observer may be further enhanced if the process of generating the virtual image is imperceptible.